CN110769506B

CN110769506B - Resource allocation method of multi-hop in-band relay system

Info

Publication number: CN110769506B
Application number: CN201810841878.6A
Authority: CN
Inventors: 袁乃华; 范晨; 陈贵荣; 魏立梅; 佟学俭
Original assignee: Chengdu TD Tech Ltd
Current assignee: Chengdu TD Tech Ltd
Priority date: 2018-07-27
Filing date: 2018-07-27
Publication date: 2022-06-03
Anticipated expiration: 2038-07-27
Also published as: CN110769506A

Abstract

The application discloses a resource allocation method of a multi-hop in-band relay system, which comprises the following steps: in a multi-hop relay system with a root node as a central node, starting from the root node, broadcasting the relay level of the system after starting step by step; the next-stage relay node determines the relay level of the next-stage relay node according to the received broadcast and reports the relay level of the next-stage relay node to the root node and the previous-stage relay node; the root node configures initial return resources for each level of relay nodes to generate a relay tree; each level of node transmits information by using the configured initial feedback resource, performs signal measurement on adjacent nodes, and reports the number of terminals accessed by each node and the data volume obtained by measurement to the root and the previous level of nodes; and the root node reallocates resources for each relay node according to the level of each relay node, the number of reported terminals and the data volume. By applying the method and the device, reasonable distribution of resources can be realized, and system performance is improved.

Description

Resource allocation method of multi-hop in-band relay system

Technical Field

The present application relates to a relay technology in a communication system, and in particular, to a resource allocation method for a multi-hop in-band relay system.

Background

In order to improve coverage, improve cell edge throughput, and perform temporary networking, 3GPP defines a single-hop relay technology. As shown in fig. 1, a Relay Node (RN) accesses a Donor Cell (Donor Cell) under the control of a Donor (Donor eNB, eNB) through a Un interface, and a UE accesses the RN through a Uu interface.

In a 3GPP single-hop relay system, an RN node takes the roles of a Uu port client and a Un port client, and needs to coordinate the allocation of air interface resources of two types of terminals of the Un port and the Uu port. Specifically, the RN node function includes time division multiplexing of the Uu port and Un port resources, and on one hand, the RN accesses the UE through the Uu port, and on the other hand, the RN uses the Un backhaul subframe to backhaul data to the DeNB. The RN can use the Un interface to backhaul data, and therefore, the functional part of the RN that backhauls data through the Un interface is called backhaul ue (rue) of the relay node.

On the basis that 3GPP only supports 1-hop in-band relay, the invention patent application entitled "multi-hop relay resource allocation method and apparatus" filed by the applicant proposes a multi-hop in-band relay system. Fig. 2 is a schematic networking diagram of a multi-hop inband relay. As shown in fig. 2, in a multi-hop relay scenario, the nth-level relay node assumes a Uu port, an nth-hop Un port, and an N-1 st-hop Un port. Time division multiplexing of the above three resources needs to be coordinated. The multi-hop RN functions as follows:

1, Uu: accessing UE through a Uu port;

2, Un (N): receiving data of a Un port of a previous hop;

un (N-1): transmitting the Uu port/previous hop Un port data to a next hop relay through Un;

for the N-level node, the Un port of the previous hop refers to the Un port between the N level and the N +1 level, the Un port of the next hop refers to the Un port between the N level and the N-1 level, and the relay of the next hop refers to the N-1 level node.

In each level of nodes in the multi-hop relay, the UE (normal UE) of the node in the level needs to be scheduled and the backhaul UE (rue) of the relay node needs to be scheduled. In a networking scene in which the root node is the central node, all communications between UEs need to pass through the root node, and the current resource allocation method cannot adapt to the networking scene, which affects system performance.

Disclosure of Invention

The application provides a resource allocation method of a multi-hop in-band relay system, which can realize reasonable allocation of resources and improve system performance.

In order to achieve the purpose, the following technical scheme is adopted in the application:

a resource allocation method of a multi-hop in-band relay system comprises the following steps:

in a multi-hop relay system with a root node as a central node, starting from the root node, broadcasting the relay level of the system after starting step by step; the next-stage relay node determines the relay level of the next-stage relay node according to the received broadcast and reports the relay level of the next-stage relay node to the root node; the root node configures initial return resources for each level of relay nodes to generate a relay tree;

each level of node transmits information by using the configured initial feedback resource, performs signal measurement on adjacent nodes, and reports the number of terminals accessed by each node and the data volume obtained by measurement to the root node and the previous level of node; and the root node reallocates the return resources for each relay node according to the level of each relay node, the number of reported terminals and the data volume.

Preferably, the initial backhaul resource is configured according to the minimum backhaul resource.

Preferably, the initial backhaul resource allocation and the backhaul resource reallocation are performed according to a collision avoidance principle of air interface resources of the relay node.

According to the technical scheme, in the multi-hop relay system with the root node as the center node, the relay level of the multi-hop relay system is broadcast after the multi-hop relay system is started from the root node step by step; the next-stage relay node determines the relay level of the next-stage relay node according to the received broadcast and reports the relay level of the next-stage relay node to the root node; the root node configures initial return resources for each level of relay nodes to generate a relay tree; each level of nodes transmits information by using the configured initial feedback resources, performs signal measurement on adjacent nodes, and reports the number of terminals accessed by each node and the data volume obtained by measurement to a root node; and the root node reallocates resources for each relay node according to the level of each relay node, the number of reported terminals and the data volume. By applying the method and the device, reasonable distribution of resources can be realized, and system performance is improved.

Drawings

Fig. 1 is a schematic diagram of a single-hop relay network;

fig. 2 is a schematic networking diagram of a multi-hop inband relay;

FIG. 3 is a schematic diagram of a networking scenario in which a root node is a central node;

FIG. 4 is a schematic diagram of a basic flow of a resource allocation method in the present application;

fig. 5 is a diagram illustrating configuration of initial backhaul resources;

fig. 6 is a diagram illustrating a return resource allocation;

fig. 7 is a schematic diagram of a relay mode resource of FDD LTE;

fig. 8 is a schematic diagram of relay mode resources for TDD LTE;

fig. 9 is a schematic diagram of the principle of avoiding collision of air interface resources.

Detailed Description

For the purpose of making the objects, technical means and advantages of the present application more apparent, the present application will be described in further detail with reference to the accompanying drawings.

Fig. 3 is a schematic diagram of a networking scenario in which a root node is a central node. In the networking scenario, all the UEs need to communicate with each other through the root node, and the relay node needs to transmit the data of the local UE to the node of the previous stage through the relay terminal, so that the data traffic of the nodes of each stage is different, and particularly, the data volume of the root node is the largest. Meanwhile, the number of stages in which the node is located is different, the relay data volume and the local data volume of the node are different and can be dynamically changed, and the resource needs allocated to the nodes at each stage can be loaded and adapted to the corresponding data volume. Based on the above analysis, the present application provides a resource allocation method for a multi-hop in-band relay system, which allocates air interface resources of Un and Uu ports according to the number of stages of nodes, the returned data volume of each stage and the data volume of locally scheduled UE, and coordinates the Un air interface resources of each stage of nodes for relaying the UE. The method is suitable for the node grade number and the data volume of different grade nodes in the multi-hop relay, better meets the data transmission requirement, and improves the system performance.

Fig. 4 is a basic flowchart of a resource allocation method according to the present application. In this flow, processing is performed based on the networking scenario shown in fig. 3, and as shown in fig. 4, the method includes:

step 401, in a multi-hop relay system with a root node as a center node, starting from the root node, broadcasting the relay level of the multi-hop relay system after starting step by step; the next-stage relay node determines the relay level of the next-stage relay node according to the received broadcast, and reports the relay level of the next-stage relay node to the root node and the previous-stage relay node.

The root node is firstly started and then broadcasted, and the next-level node generates and reports the relay level of the next-level node after receiving the broadcast of the root node and broadcasts the relay level of the next-level node. And (5) gradually descending, starting the node and reporting the relay level in sequence.

After determining the relay level of each node, each node reports the relay level to the previous node and reports the relay level to the root node layer by layer, so that the root node can determine the relay level of each node.

Step 402, the root node configures initial backhaul resources for each stage of relay nodes to generate a relay tree.

Preferably, the initial backhaul resource may be configured according to the minimum backhaul resource when configuring the initial backhaul resource, and the backhaul resource configuration of each stage of relay node is required to conform to the collision avoidance principle. Through the method, the paths of the relay nodes and the root node are opened, the root node generates the multi-hop relay topology tree according to the node level numerical values reported by the nodes, and the whole communication link is opened. In addition, the processing of this step may be interleaved with or performed simultaneously with the partial processing of step 401. For example, a node a at a certain level receives a broadcast from a previous level and reports its own level, a root node configures an initial backhaul resource for the node a, and the node a broadcasts to a next level. The process of configuring the initial backhaul resource for the node a by the root node (corresponding to step 402) and the process of broadcasting to the next level by the node a (part of the content of step 401) may be performed simultaneously or in any order.

After the processing of

steps

401 and 402, a relay tree is generated and the configuration of the initial backhaul resource is implemented, as shown in fig. 5.

And step 403, each level of node performs information transmission by using the configured initial backhaul resource, performs signal measurement on neighboring nodes, and reports the number of terminals and data volume of each node to be accessed, which are obtained through measurement, to the root node and the previous level of node.

After the initial backhaul resource configuration is performed in step 402, the communication link from the root node to each level of nodes is opened, and information transmission is possible. In the multi-hop relay system, the levels of nodes at all levels are different, and the number of accessed terminals and the data volume are greatly different, so that the node levels, the number of accessed terminals, the data transmission volume and the like are taken into consideration of resource allocation, and therefore, the nodes at all levels are required to measure and report corresponding information.

And step 404, the root node reallocates resources for each relay node according to the level of each relay node, the number of reported terminals and the data volume.

After the grades of all levels of relay nodes, the number of accessed terminals and the transmitted data amount are counted, the root node can reallocate return resources for each relay node according to the node tree and the grade number of each node in the node tree by referring to the signal measurement of relay UE of each node to the adjacent relay node and the principle of avoiding collision of empty resource of the relay node, so that the allocation of the return resources can adapt to the grade of each node, the number of accessed terminals and the transmitted data amount, the effectiveness of information transmission is ensured, and the system performance is improved. Fig. 6 shows a schematic diagram of the backhaul resource reallocation in the networking scenario of fig. 3.

In addition, when configuring backhaul resources for the relay node, the backhaul resources may be selected from existing backhaul resource tables, for example, relay mode resource tables of FDD and TDD LTE. Specifically, there are 24 available subframes within 40ms of the 3GPP FDD RN backhaul subframe. The 3GPP FDD modulo the 8ms period divides the RN backhaul subframe into 8 patterns, as shown in table 1 and fig. 7. For each Pattern subframe, 0,4,5, and 9 subframes need to be avoided. For example, pattern 0 contains {8,16,24,32, and the actual value is {8,16,32 }. The node of the relay may choose one or more of the 8 modes as the Un backhaul resource.

The 3GPP TDD Un resources are configured with a period of 10ms, as shown in table 2 and fig. 8. TDD can extend the existing single-hop 10ms mode to 20ms, 40ms modes; the relaying node may choose one or more of 4 (20ms) or 8 (40ms) modes as the Un backhaul resource.

The air interface resource collision avoidance principle of each relay node RN may specifically be: in multi-stage relay, the sub-frames of the Uu port, Un (N), Un (N-1) of the RN node cannot collide. When the sub-frame allocation of each interface is performed, the following conditions need to be satisfied:

a Uu opening: keeping the timing relation of the uplink and downlink channels of the common UE unchanged;

un (N-1) port: the occupied sub-frame does not conflict with Uu, Un (N), Un (N + 1);

un (N) port: the occupied sub-frame does not conflict with Uu, Un (N-1) and Un (N + 2).

That is, in the scenario that the RN supports multiple carriers, it is necessary to avoid the Un (N-1) transmission interference Un (N) port reception with the RN, or vice versa. It is constrained that two Un ports of the same RN cannot use the same Pattern with the same frequency or different frequencies. For example, as shown in fig. 9, when the level 1 RN transmits to the level 0 RN, the transmission signal of the level 1 RN may be received by the level 2 RN, at this time, the level 3 RN cannot transmit by using a Pattern unified with the level 1 RN, otherwise, the reception of the level 2 RN may be affected; meanwhile, when the level 1 RN transmits, the level 0 RN needs to perform receiving processing and cannot collide with the level 1 RN.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A resource allocation method of a multi-hop in-band relay system is characterized by comprising the following steps:

each level of node transmits information by using the configured initial feedback resource, performs signal measurement on adjacent nodes, and reports the number of terminals accessed by each node and the data volume obtained by measurement to the root node and the previous level of node; the root node reallocates the return resources for each relay node according to the level of each relay node, the number of reported terminals and the data volume;

the method comprises the steps that configuration is carried out according to minimum backhaul resources when initial backhaul resources are configured, and configuration of the initial backhaul resources and reallocation of the backhaul resources are carried out according to a collision avoidance principle of air interface resources of a relay node; the principle of avoiding collision of the air interface resources of the relay node is as follows: in the multi-stage relay, the sub-frames of the Uu port, Un (N) and Un (N-1) of the RN node cannot collide, and the following conditions are met when the sub-frames of each interface are allocated: the timing relation of the uplink and downlink channels of the UE is kept unchanged at the Uu port, the subframe occupied by the Un (N-1) port does not conflict with the Uu, the Un (N) port and the Un (N +1), and the subframe occupied by the Un (N) port does not conflict with the Uu, the Un (N-1) port and the Un (N + 2).